Re: Laterite/vermiculite mix

Miles Morrissey wrote:

>        Secondly, After reading Jim Kelly's soil and  vermiculite  posts
>and more recently  his article in the last TAG on  soil characteristics,
>I am thinking of mixing the laterite I have with vermiculite.  My theory
>is that this mixture will have an increased cation exchange capacity than
>laterite alone.  What are peoples thoughts?  A discussion of pro's and
>con's would be appreciated.

I don't know about the cation exchange capacity. I used Jim Kelley's method
and it has worked great. The only thing I would change is  the mechanical
characteristics of the substrate. The soil vermicilite soup flows too
easily when plants are uprooted.

Next time I would:

1) Put the vermiculite in a blender so it breaks up the chunks better.

2) Add 5 mm gravel to the soil and powdered vermiculite soup for mechanical
stability, and make the gravel and soup layer deeper and use less gravel
over it. I've noticed that the soil eventually falls down into the gravel
when it is disturbed, and I think with a coarse gravel and soil only, the
substrate would be more self repairing.

I uprooted an Echindorous Amazonius that had grown too big for my 29
gallon. The roots held onto the vermiculite pretty well, and a big mud ball
came up with it. It was a mess.


Paul Nicholson              Electronic Imaging Systems, Inc.
paul at eisusa_com             5148 Commerce Avenue, Unit F
TEL 805 532 1068            Moorpark, CA 93021 U.S.A.
FAX 805 532 1065

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